A present method of acquiring, storing and analyzing RF signals is to down-convert an RF signal to an intermediate frequency (IF) by local oscillator mixing for sampling and digitization using existing technology. The digital words generated by the analog to digital conversion process are stored in a digital memory. Once stored the contents may by accessed by a processor unit and analyzed. The drawback of this method is a limitation on the maximum instantaneous bandwidth. Since the process involves down conversation and serial digitization, the maximum instantaneous bandwidth is set by the speed of the current digitization, analog-to-digital (A/D) conversion and digital memory processes. This limits the instantaneous bandwidth to several hundred MHz.
Another method of acquiring, storing and analyzing RF signals employs the strobe principle as employed in sampling oscilloscopes. In sampling oscilloscopes, a voltage sample is taken at a discrete point on an input signal. Subsequent waveforms are sampled at later discrete points in order to obtain the overall waveforms. A drawback of this method is that, although it is capable of handling extremely wide instantaneous bandwidths, the technique is restricted to repetitive signals. It cannot handle transient signals or complex waveforms which vary continuously.